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Finding the Fourth Proportional to 30, 45 and 11

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Solution

The fourth proportional to 30, 45 and 11 is: 16.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    30 : 45 = 11 : x
  2. Step 2: Convert to fraction form
    30/45 = 11/x
  3. Step 3: Cross multiply
    30x = 45 × 11
  4. Step 4: Simplify right side
    30x = 495
  5. Step 5: Solve for x
    x = 495/30
  6. Step 6: Final answer
    x = 16.50

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.